Study the effect of a vaccine consisting of BCG cell wall in water/mineral oil emulsion on the development of malignant bovine ocular squamous cell carcinoma from benign precursor lesions. Utilizing four experimental animal groups (total 240 cattle), evaluate the prophylactic benefit provided by the vaccine. These include animals receiving: active BCG cell wall vaccine; inactive, sham BCG vaccine; no treatment; and surgical removal of the benign lesion. At monthly intervals, monitor each animal for immunologic status by skin testing with DNCB and PPD. Collect and cryopreserve for later examination at the discretion of the Project Officer: tumor tissues; lymphocytes; peritoneal cells; serum; and red cells.